Foxboro P0903AA Control Module
Termination Assemblies and Cables
Field I/O signals connect to the FBM subsystem via DIN rail mounted termination
assemblies (TAs). Multiple types of TAs are available with FBM217 to provide input
signal connections, signal conditioning, optical isolation from signal surges and
external power connections for field devices. Since these features are built into the
termination assemblies (where required), in most applications there is no need for
additional termination equipment for field circuit functions such as circuit protection or
signal conditioning (including fusing and power distribution).
The termination assembly can be used with a single FBM217 or with a redundant pair
(two FBM217s).
The DIN rail mounted termination assemblies connect to the FBM subsystem
baseplate by means of removable termination cables. When used with a redundant
module pair, the termination assembly is connected to the baseplate using a
redundant adapter (RH926ZY).
The cables are available in a variety of lengths, up to 30 meters (98 feet), allowing the
termination assemblies to be mounted in either the enclosure or in an adjacent
enclosure. See Functional Specifications- Termination Assemblies, page 14 for
termination cable part numbers and specifications.
Migration Use of Termination Assemblies
WhenanFBM217isusedto replace 100 Series FBMs, its associated termination
assembly is determined based on which 100 Series FBM is being replaced. Typically,
the 100 Series FBM being replaced was a main FBM and may have been used in
conjunction with an expansion FBM.
Asingle FBM217 provides the I/O communications for both the 100 Series equivalent
main and expansion TAs. To provide enough terminals for the field input wiring, two
termination assemblies are used with the FBM217- one for the field input wiring for
the replaced main FBM, and one for the field input wiring for the replaced expansion
FBM.
The “expansion” termination assembly is daisy-chained to the “main” termination
assembly via the expansion cables listed in Table 3. page 20.
See Functional Specifications- Termination Assemblies, page 14 for a list of the
termination assemblies needed to replace both the 100 Series main FBMs and the
expansion FBMs.
Alternatively, the FBM217 can accept field wiring through a Termination Assembly
Adapter (TAA) instead of the termination assemblies when upgrading 100 Series
FBMs. This is discussed in Termination Assembly Adapter Modules for 100 Series
Upgrade (PSS 41H-2W4)
Cable Connection
Type 4:
• FBMBaseplate End:
37-pin D-subminiature plug
• Termination Assembly End:
37-pin D-subminiature receptacle
Construction
Termination
Assembly
Field Termination
Connections
• Material:
Polyamide (PA), compression
Compression — Accepted Wiring Sizes:
• Solid/Stranded/AWG:
0.2 to 4 mm
Type 6:
• MainTAEnd:
25-pin D-subminiature receptacle
• Expansion TAEnd:
37-pin D-subminiature receptacle
2
/0.2 to 2.5 mm
2
• Stranded with Ferrules:
0.2 to 2.5 mm
2
/24 to 12 AWG
with or without plastic collar